1 /* AF_RXRPC sendmsg() implementation.
3 * Copyright (C) 2007, 2016 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public Licence
8 * as published by the Free Software Foundation; either version
9 * 2 of the Licence, or (at your option) any later version.
12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14 #include <linux/net.h>
15 #include <linux/gfp.h>
16 #include <linux/skbuff.h>
17 #include <linux/export.h>
19 #include <net/af_rxrpc.h>
20 #include "ar-internal.h"
23 RXRPC_CMD_SEND_DATA, /* send data message */
24 RXRPC_CMD_SEND_ABORT, /* request abort generation */
25 RXRPC_CMD_ACCEPT, /* [server] accept incoming call */
26 RXRPC_CMD_REJECT_BUSY, /* [server] reject a call as busy */
30 * wait for space to appear in the transmit/ACK window
31 * - caller holds the socket locked
33 static int rxrpc_wait_for_tx_window(struct rxrpc_sock *rx,
34 struct rxrpc_call *call,
37 DECLARE_WAITQUEUE(myself, current);
41 call->tx_hard_ack, call->tx_top, call->tx_winsize);
43 add_wait_queue(&call->waitq, &myself);
46 set_current_state(TASK_INTERRUPTIBLE);
48 if (call->tx_top - call->tx_hard_ack <
49 min_t(unsigned int, call->tx_winsize,
50 call->cong_cwnd + call->cong_extra))
52 if (call->state >= RXRPC_CALL_COMPLETE) {
56 if (signal_pending(current)) {
57 ret = sock_intr_errno(*timeo);
61 trace_rxrpc_transmit(call, rxrpc_transmit_wait);
62 release_sock(&rx->sk);
63 *timeo = schedule_timeout(*timeo);
67 remove_wait_queue(&call->waitq, &myself);
68 set_current_state(TASK_RUNNING);
74 * Schedule an instant Tx resend.
76 static inline void rxrpc_instant_resend(struct rxrpc_call *call, int ix)
78 spin_lock_bh(&call->lock);
80 if (call->state < RXRPC_CALL_COMPLETE) {
81 call->rxtx_annotations[ix] = RXRPC_TX_ANNO_RETRANS;
82 if (!test_and_set_bit(RXRPC_CALL_EV_RESEND, &call->events))
83 rxrpc_queue_call(call);
86 spin_unlock_bh(&call->lock);
90 * Queue a DATA packet for transmission, set the resend timeout and send the
93 static void rxrpc_queue_packet(struct rxrpc_call *call, struct sk_buff *skb,
96 struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
97 rxrpc_seq_t seq = sp->hdr.seq;
99 u8 annotation = RXRPC_TX_ANNO_UNACK;
101 _net("queue skb %p [%d]", skb, seq);
103 ASSERTCMP(seq, ==, call->tx_top + 1);
106 annotation |= RXRPC_TX_ANNO_LAST;
108 /* We have to set the timestamp before queueing as the retransmit
109 * algorithm can see the packet as soon as we queue it.
111 skb->tstamp = ktime_get_real();
113 ix = seq & RXRPC_RXTX_BUFF_MASK;
114 rxrpc_get_skb(skb, rxrpc_skb_tx_got);
115 call->rxtx_annotations[ix] = annotation;
117 call->rxtx_buffer[ix] = skb;
120 trace_rxrpc_transmit(call, rxrpc_transmit_queue_last);
122 trace_rxrpc_transmit(call, rxrpc_transmit_queue);
124 if (last || call->state == RXRPC_CALL_SERVER_ACK_REQUEST) {
125 _debug("________awaiting reply/ACK__________");
126 write_lock_bh(&call->state_lock);
127 switch (call->state) {
128 case RXRPC_CALL_CLIENT_SEND_REQUEST:
129 call->state = RXRPC_CALL_CLIENT_AWAIT_REPLY;
131 case RXRPC_CALL_SERVER_ACK_REQUEST:
132 call->state = RXRPC_CALL_SERVER_SEND_REPLY;
135 case RXRPC_CALL_SERVER_SEND_REPLY:
136 call->state = RXRPC_CALL_SERVER_AWAIT_ACK;
141 write_unlock_bh(&call->state_lock);
144 if (seq == 1 && rxrpc_is_client_call(call))
145 rxrpc_expose_client_call(call);
147 ret = rxrpc_send_data_packet(call, skb, false);
149 _debug("need instant resend %d", ret);
150 rxrpc_instant_resend(call, ix);
152 ktime_t now = ktime_get_real(), resend_at;
154 resend_at = ktime_add_ms(now, rxrpc_resend_timeout);
156 if (ktime_before(resend_at, call->resend_at)) {
157 call->resend_at = resend_at;
158 rxrpc_set_timer(call, rxrpc_timer_set_for_send, now);
162 rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
167 * send data through a socket
168 * - must be called in process context
169 * - caller holds the socket locked
171 static int rxrpc_send_data(struct rxrpc_sock *rx,
172 struct rxrpc_call *call,
173 struct msghdr *msg, size_t len)
175 struct rxrpc_skb_priv *sp;
177 struct sock *sk = &rx->sk;
182 timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
184 /* this should be in poll */
185 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
187 if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))
190 more = msg->msg_flags & MSG_MORE;
192 skb = call->tx_pending;
193 call->tx_pending = NULL;
194 rxrpc_see_skb(skb, rxrpc_skb_tx_seen);
198 /* Check to see if there's a ping ACK to reply to. */
199 if (call->ackr_reason == RXRPC_ACK_PING_RESPONSE)
200 rxrpc_send_ack_packet(call);
203 size_t size, chunk, max, space;
207 if (call->tx_top - call->tx_hard_ack >=
208 min_t(unsigned int, call->tx_winsize,
209 call->cong_cwnd + call->cong_extra)) {
211 if (msg->msg_flags & MSG_DONTWAIT)
213 ret = rxrpc_wait_for_tx_window(rx, call,
219 max = RXRPC_JUMBO_DATALEN;
220 max -= call->conn->security_size;
221 max &= ~(call->conn->size_align - 1UL);
224 if (chunk > msg_data_left(msg) && !more)
225 chunk = msg_data_left(msg);
227 space = chunk + call->conn->size_align;
228 space &= ~(call->conn->size_align - 1UL);
230 size = space + call->conn->security_size;
232 _debug("SIZE: %zu/%zu/%zu", chunk, space, size);
234 /* create a buffer that we can retain until it's ACK'd */
235 skb = sock_alloc_send_skb(
236 sk, size, msg->msg_flags & MSG_DONTWAIT, &ret);
240 rxrpc_new_skb(skb, rxrpc_skb_tx_new);
242 _debug("ALLOC SEND %p", skb);
244 ASSERTCMP(skb->mark, ==, 0);
246 _debug("HS: %u", call->conn->security_size);
247 skb_reserve(skb, call->conn->security_size);
248 skb->len += call->conn->security_size;
252 if (sp->remain > skb_tailroom(skb))
253 sp->remain = skb_tailroom(skb);
255 _net("skb: hr %d, tr %d, hl %d, rm %d",
261 skb->ip_summed = CHECKSUM_UNNECESSARY;
267 /* append next segment of data to the current buffer */
268 if (msg_data_left(msg) > 0) {
269 int copy = skb_tailroom(skb);
270 ASSERTCMP(copy, >, 0);
271 if (copy > msg_data_left(msg))
272 copy = msg_data_left(msg);
273 if (copy > sp->remain)
277 ret = skb_add_data(skb, &msg->msg_iter, copy);
286 /* check for the far side aborting the call or a network error
288 if (call->state == RXRPC_CALL_COMPLETE)
289 goto call_terminated;
291 /* add the packet to the send queue if it's now full */
292 if (sp->remain <= 0 ||
293 (msg_data_left(msg) == 0 && !more)) {
294 struct rxrpc_connection *conn = call->conn;
298 /* pad out if we're using security */
299 if (conn->security_ix) {
300 pad = conn->security_size + skb->mark;
301 pad = conn->size_align - pad;
302 pad &= conn->size_align - 1;
303 _debug("pad %zu", pad);
305 memset(skb_put(skb, pad), 0, pad);
308 seq = call->tx_top + 1;
312 sp->hdr.flags = conn->out_clientflag;
314 if (msg_data_left(msg) == 0 && !more)
315 sp->hdr.flags |= RXRPC_LAST_PACKET;
316 else if (call->tx_top - call->tx_hard_ack <
318 sp->hdr.flags |= RXRPC_MORE_PACKETS;
320 ret = conn->security->secure_packet(
321 call, skb, skb->mark, skb->head);
325 rxrpc_queue_packet(call, skb, !msg_data_left(msg) && !more);
328 } while (msg_data_left(msg) > 0);
333 call->tx_pending = skb;
334 _leave(" = %d", ret);
338 rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
339 _leave(" = %d", -call->error);
353 * extract control messages from the sendmsg() control buffer
355 static int rxrpc_sendmsg_cmsg(struct msghdr *msg,
356 unsigned long *user_call_ID,
357 enum rxrpc_command *command,
361 struct cmsghdr *cmsg;
362 bool got_user_ID = false;
365 *command = RXRPC_CMD_SEND_DATA;
367 if (msg->msg_controllen == 0)
370 for_each_cmsghdr(cmsg, msg) {
371 if (!CMSG_OK(msg, cmsg))
374 len = cmsg->cmsg_len - CMSG_ALIGN(sizeof(struct cmsghdr));
375 _debug("CMSG %d, %d, %d",
376 cmsg->cmsg_level, cmsg->cmsg_type, len);
378 if (cmsg->cmsg_level != SOL_RXRPC)
381 switch (cmsg->cmsg_type) {
382 case RXRPC_USER_CALL_ID:
383 if (msg->msg_flags & MSG_CMSG_COMPAT) {
384 if (len != sizeof(u32))
386 *user_call_ID = *(u32 *) CMSG_DATA(cmsg);
388 if (len != sizeof(unsigned long))
390 *user_call_ID = *(unsigned long *)
393 _debug("User Call ID %lx", *user_call_ID);
398 if (*command != RXRPC_CMD_SEND_DATA)
400 *command = RXRPC_CMD_SEND_ABORT;
401 if (len != sizeof(*abort_code))
403 *abort_code = *(unsigned int *) CMSG_DATA(cmsg);
404 _debug("Abort %x", *abort_code);
405 if (*abort_code == 0)
410 if (*command != RXRPC_CMD_SEND_DATA)
412 *command = RXRPC_CMD_ACCEPT;
417 case RXRPC_EXCLUSIVE_CALL:
434 * Create a new client call for sendmsg().
436 static struct rxrpc_call *
437 rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg,
438 unsigned long user_call_ID, bool exclusive)
440 struct rxrpc_conn_parameters cp;
441 struct rxrpc_call *call;
444 DECLARE_SOCKADDR(struct sockaddr_rxrpc *, srx, msg->msg_name);
449 return ERR_PTR(-EDESTADDRREQ);
452 if (key && !rx->key->payload.data[0])
455 memset(&cp, 0, sizeof(cp));
456 cp.local = rx->local;
458 cp.security_level = rx->min_sec_level;
459 cp.exclusive = rx->exclusive | exclusive;
460 cp.service_id = srx->srx_service;
461 call = rxrpc_new_client_call(rx, &cp, srx, user_call_ID, GFP_KERNEL);
463 _leave(" = %p\n", call);
468 * send a message forming part of a client call through an RxRPC socket
469 * - caller holds the socket locked
470 * - the socket may be either a client socket or a server socket
472 int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
474 enum rxrpc_command cmd;
475 struct rxrpc_call *call;
476 unsigned long user_call_ID = 0;
477 bool exclusive = false;
483 ret = rxrpc_sendmsg_cmsg(msg, &user_call_ID, &cmd, &abort_code,
488 if (cmd == RXRPC_CMD_ACCEPT) {
489 if (rx->sk.sk_state != RXRPC_SERVER_LISTENING)
491 call = rxrpc_accept_call(rx, user_call_ID, NULL);
493 return PTR_ERR(call);
494 rxrpc_put_call(call, rxrpc_call_put);
498 call = rxrpc_find_call_by_user_ID(rx, user_call_ID);
500 if (cmd != RXRPC_CMD_SEND_DATA)
502 call = rxrpc_new_client_call_for_sendmsg(rx, msg, user_call_ID,
505 return PTR_ERR(call);
508 _debug("CALL %d USR %lx ST %d on CONN %p",
509 call->debug_id, call->user_call_ID, call->state, call->conn);
511 if (call->state >= RXRPC_CALL_COMPLETE) {
512 /* it's too late for this call */
514 } else if (cmd == RXRPC_CMD_SEND_ABORT) {
516 if (rxrpc_abort_call("CMD", call, 0, abort_code, ECONNABORTED))
517 ret = rxrpc_send_abort_packet(call);
518 } else if (cmd != RXRPC_CMD_SEND_DATA) {
520 } else if (rxrpc_is_client_call(call) &&
521 call->state != RXRPC_CALL_CLIENT_SEND_REQUEST) {
522 /* request phase complete for this client call */
524 } else if (rxrpc_is_service_call(call) &&
525 call->state != RXRPC_CALL_SERVER_ACK_REQUEST &&
526 call->state != RXRPC_CALL_SERVER_SEND_REPLY) {
527 /* Reply phase not begun or not complete for service call. */
530 ret = rxrpc_send_data(rx, call, msg, len);
533 rxrpc_put_call(call, rxrpc_call_put);
534 _leave(" = %d", ret);
539 * rxrpc_kernel_send_data - Allow a kernel service to send data on a call
540 * @sock: The socket the call is on
541 * @call: The call to send data through
542 * @msg: The data to send
543 * @len: The amount of data to send
545 * Allow a kernel service to send data on a call. The call must be in an state
546 * appropriate to sending data. No control data should be supplied in @msg,
547 * nor should an address be supplied. MSG_MORE should be flagged if there's
548 * more data to come, otherwise this data will end the transmission phase.
550 int rxrpc_kernel_send_data(struct socket *sock, struct rxrpc_call *call,
551 struct msghdr *msg, size_t len)
555 _enter("{%d,%s},", call->debug_id, rxrpc_call_states[call->state]);
557 ASSERTCMP(msg->msg_name, ==, NULL);
558 ASSERTCMP(msg->msg_control, ==, NULL);
562 _debug("CALL %d USR %lx ST %d on CONN %p",
563 call->debug_id, call->user_call_ID, call->state, call->conn);
565 if (call->state >= RXRPC_CALL_COMPLETE) {
566 ret = -ESHUTDOWN; /* it's too late for this call */
567 } else if (call->state != RXRPC_CALL_CLIENT_SEND_REQUEST &&
568 call->state != RXRPC_CALL_SERVER_ACK_REQUEST &&
569 call->state != RXRPC_CALL_SERVER_SEND_REPLY) {
570 ret = -EPROTO; /* request phase complete for this client call */
572 ret = rxrpc_send_data(rxrpc_sk(sock->sk), call, msg, len);
575 release_sock(sock->sk);
576 _leave(" = %d", ret);
579 EXPORT_SYMBOL(rxrpc_kernel_send_data);
582 * rxrpc_kernel_abort_call - Allow a kernel service to abort a call
583 * @sock: The socket the call is on
584 * @call: The call to be aborted
585 * @abort_code: The abort code to stick into the ABORT packet
586 * @error: Local error value
587 * @why: 3-char string indicating why.
589 * Allow a kernel service to abort a call, if it's still in an abortable state.
591 void rxrpc_kernel_abort_call(struct socket *sock, struct rxrpc_call *call,
592 u32 abort_code, int error, const char *why)
594 _enter("{%d},%d,%d,%s", call->debug_id, abort_code, error, why);
598 if (rxrpc_abort_call(why, call, 0, abort_code, error))
599 rxrpc_send_abort_packet(call);
601 release_sock(sock->sk);
605 EXPORT_SYMBOL(rxrpc_kernel_abort_call);